Combination tool



July 2, 1946.

I I v COMBINATION TOOL Filed Oct. 16; 1943.

2 Shets-Sheet 1 P. w. YANKUN 2,403,254

Patented July 2. 1946 UNITED STATES PATENT OFFICE.

COMBINATION TOOL V Peter W. Yankun, Dorchester, Mass.

Application October 16, 1943, Serial N 0. 506,475

1 Claim. 1

This invention relates to a combination tool which can be used. either as a pair of dividers or as a pair of calipers or as a pair of compasses.

One object of the invention is to provide a novel tool of this character which is relatively simple in construction and can be easily converted from a pair of dividers to a pair of calipers or to a pair of compasses.

Other objects of the invention are to improve generally combination tools of this type in the particulars more fully hereinafter set forth.

In the drawings wherein I have illustrated an embodiment of the invention:

Fig. 1 is a view of an instrument embodying my invention showing it in the form of a pair of calipers.

Fig. 2 is an enlarged section on the line 2-2, Fig. 1.

Fig. 3 is a fragmentary View showing the end of one of the legs.

Fig. 4 is a sectional view through the lower end of one of the legs.

Fig. 5 is a transverse section through one of the legs illustrating the action of the clamping screw in clamping the extension elements in position.

Fig. 6 is a view partly in section showing the instrument in the form of a pair of dividers.

Fig. '7 is a view illustrating the extension elements by which the instrument is converted into a pair of calipers for large work.

Fig. 8 is a view illustrating the pencil holder which may be used when the implement is converted into a pair of compasses.

My improved tool comprises a main body portion presenting two legs 3 and 4, which are pivotally connected together as shown at 5 so that the legs can be swung toward and from each other.

Each leg is adapted to carry an extension element, and these elements may be in the form of divider points, such as shown at 6, 0r caliper points for small world such as shown at I, or caliper points for large work such as shown at 8. These extension elements, whether in the nature of divider points, caliper points or compass points, are detachably carried by the legs 3 and 4 and are interchangeable so that either leg 3 or 4 may be provided with an extension element of either type.

The manner in which these extension elements are attached to the legs 3 and 4 will be hereinafter described.

The leg 3 has secured thereto a screw-threaded member 9 which extends through a boss In carried by the leg 4, said screw having an adjusting nut l l screw-threaded thereto for controlling the spread of the legs 3 and 4.

The boss I0 is shown as formed with an extension l-2' which has an enlarged end I3- that is formed in its outer face with a conical recess I4. The nut l l is provided with a conical end portion l5 adapted to fit into the conical recess [4. The enlarged end i3 of the boss extension I2 is provided with an indication mark it and the nut ll may be provided with one or more graduation marks ll, thereby providing a micrometer adjustment for controlling the spread of the legs 3 and 4.

These legs are acted upon by a suitable spring tending to spread them as usual in instruments of this type, said spring serving to maintain the enlarged end l3 of the boss extension in contact with the nut II.

This spring is indicated at I3 and it is in the nature of a coil spring which occupies a recess l9 in the leg 4. One end 20 of this spring bears against the inner face of the leg 4 and the other end 21 of the spring bears against the inner face of the leg 3. The end 20 of the spring occupies a recess 52 which serves to retain it in position and the longer end 2! of the spring extends through an aperture in a projection 22 carried by the inner face of the arm 3'. The inner face of the arm 4 is formed with a recess 23 to receive the projection 22 when the legs are closed together, and said inner face of the leg 3 may also be provided with an elongated recess 24 to receive the end 2i of the spring when the legs are closed together.

While the screw 9' may be attached to the leg 3 in any convenient way, I have herein shown the end of the screw extending loosely through a transverse opening in an anchoring member 25 which is secured to the legs by a screw 2bv that passes through an opening in the end of the adjusting screw 9'; This connection allows the screw fl'to have'a slight swinging movement such as. is required as the legs 3 and 4 are moved toward and from each other.

The boss I ll may be attached to the leg 4 by any appropriate means. One simple construction for this purpose is shown in the drawings and comprises a screw 27 which extends through the leg 4 and screws into the boss.

Thi boss to is provided with a set screw 28 by which the screw 9 can be clamped to the boss Ill. The said screw is shown as having a, flattened face 29 against which the said screw 28 impinges when it is tightened.

Each of the legs 3 and 4 is provided on its outer face with a groove or channel 30 to receive'the shank of one of the extension elements. Each groove 30 has cylindrical walls and is therefore of a shape to fit a round or cylindrical shank. Each of the extension members 6, 1, and 8 is provided with a cylindrical shank portion 3| of a size to fit within the groove 30. The cylindrical walls of each groove or channel 30 subtend an arc of more than 180, thereby providing lips 60 which embrace the shank 3|.

Each leg member 3 or 4 is formed at its lower end with a lateral extension 32 having an opening 33 therethrough which registers with the corre: sponding groove 30, With this construction the shank portion 3| of any extension member can be inserted into the groove or channel 3|) only by 33 and then moving said extension member in the direction of its length to bring it to the desired adjusted position. Similarl each leg extension can be withdrawn from its groove or channel 30 only by a movement in the direction of its length. The fact that the shankportion of each extension member is enclosed entirely by the walls of the opening 33 and is embraced by the lips 60 procurved end are directed outwardly as shown in the leg to which it is attached.

To convert the instrument into a pair of compasses, a divider point 6 will be attached to one of introducing the end thereof through the opening the legs 3 or 4 and a pencil holder element 39 will be attached to the other leg. This pencil holder element comprises a body portion '40 having a cylindrical shank 4| extending therefrom which can be entered through the opening 33 into the groove of one of the legs. The body portion is also provided with a pencil receiving groove'43 adapted to receive a pencil 44. This pencil is clamped in position by a clamping screw 45 which extends through an opening in an ear 46 carried by the body on one side of the groove and has screw-threaded engagement with a corresponding ear on the other side of the groove.

The advantage of the construction shown wherein the shank portions of the extension members are carried in grooves 3|l on the outer opening 33 and is also provided with a tapered portion 31 adapted to' irictionally engage the shank of an extension member when the clamping member is tightened. Each clamping element 34 has a knurled head 5310;; which it can be manipulated, V V

VVhen the instrument is to be used as a pair of dividers, the divider points 6 will be used as shown in Fig, 6. the shanks 3| of such points being inserted throughthe openings 33 and into thegrooves 30. a It will be understood, of course,

' that these divider points will be adjusted longitudinally of the grooves to produce divider legs of the desired length after which each divider point will be clamped inposition'by tightening its clamping screw 34.

, To convert the instrument from a pair of dividers into a pair of calipers for small objects, the divider points 6 will be removed from the legs 3 and 4, and the shank portions 3| of the caliper points I will be inserted through the openings 33 and into the grooves 30, such caliper points bein clamped in desired position by means of the clamping members 34 (see Fig. 1).

For calipering the outside diameter of an article these caliper points 1 will be adjusted with the curved ends 31 directed inwardly or toward each other as shown in dotted lines in Fig. 1. By portioning the caliper points so that the faces of the legs 3 and 4 is' that extension elements of a length to provide relatively long legs 7 can be adjusted into a position to provide relatively short legs without causing any interfere ence, In Fig. 6, for instance,the divider points are shown in dotted lines as adjusted to produce divider legs of considerable length. If the divider is to be used for small work which can be best accomplished with relatively short dividerlegs, said legs may be moved backwardly into the full line position shown in Fig. 6. When in this position, the ends of the shanks 3| of the divider points project beyond the pivotal end 5 of the legs 3 and4, but because the divider points are carried in grooves on the outer faces of the legs such prooccupying said, recess and having a short end and a long end, the short end of the spring engaging the inner face of the leg having the recess and the long end of said spring engaging the inner face of the other leg at a point further removed from the pivotal connection of the legs than the location of thev spring, a guidingprojection carried by said other leg and having an opening through which the long end of the spring extends, and an interchangeable extension element removably secured to each leg.

PETER W. YANKUN. 

